We Brought Aerospace Technology to Air Bearing systems

Air Bushings Design and installation guide

Design With Air Bushings

Typical Configurations consist of one shaft and one bushing or two parallel shafts with two to four bushings.

Usually the Air Bushings are inserted inside a Mounting block or inside the bore of a customer-designed housing. The customer designed housing must be designed so that the air supply is forced into the air ports of the bushings.
The three methods of installation are epoxy, o-rings or light press fit. OAV Mounting blocks allow for epoxy and o'ring methods of installation. In most cases it is recommended to design using o-rings because o-rings have self-aligning features and can be readjusted.

Designing with epoxy: If epoxy is used, make sure that the epoxy grooves on the bushings can be accessed with a syringe. Designing with o-rings: If o-rings are used, make sure to use the appropriate bore size and tolerance. OAV can provide this information.

Other considerations: Air bushings rely on straightness of the shaft. Design so that deflection/displacement of the shaft is minimal.

Installing bushings with o-rings:

1) First do a quick visual inspection to assure there are no sharp edges in the bore of the mounting block. The o-rings provide a very tight fit and if they get damaged, they will not work properly.
2) Lubricate the o-rings and surfaces with alcohol.
3) Press-fit the bushing inside the mounting block.
4) Insert the shaft and apply the air pressure. 30 PSI is enough to test the bushing without any load being applied.
5) Use proper alignment. If two shafts are used side-by-side, it is best to use gages to assure that the shafts are at equal distance at both ends. Parallelism is crucial for the performance of the air bushings.

Installing bushings with epoxy:

1) Clean the surfaces with alcohol.
2) Slide the air bushing into the mounting block and the shaft into the bushing.
3) Align the shaft(s) with the best parallelism possible. If two shafts are used side-by-side, it is best to use gages to assure that the shafts are at equal distance at both ends. Parallelism is crucial for the performance of the air bushings.
4) Turn the air supply on at 30 PSI and do not apply any load to the bushing.
5) Use a syringe to apply the epoxy through the syringe holes on the mounting block until the epoxy fills the epoxy grooves on the bushing. Make sure that the air port on the bushing lines up with the air port on the mounting block.
6) Keep the air supply on at 30 PSI until the epoxy cures.

Installing bushings with light Press Fit:

1) Clean the surfaces with alcohol.
2) light press fit air bushing into the mounting block and the shaft into the bushing.
3) Align the shaft(s) with the best parallelism possible. If two shafts are used side-by-side, it is best to use gages to assure that the shafts are at equal distance at both ends. Parallelism is crucial for the performance of the air bushings.
4) Make sure that the air port on the bushing lines up with the clearance hole on the mounting block.
5) install air fitting directly to OAV Air bushings as shown above